Thanks for the replies everyone, I really appreciate the first hand advice. The only reason I would get the R3M over the R2M is because I don't think I would use the 35mm frameline and would just pick up the 40mm.
I was cruising the auction site and found a few M6s, what would be a fair price for a body in near mint condition? The reason I ask is because there is such a big range in prices that I am finding.
Also, I have began to look at the Zeiss Ikon again. Has anyone had any issues with the electronic shutter? Personally I would like to steer clear of an electronic shutter camera but if reliability is not an issue then I would be okay with it.
Finally if I were to purchase a used M6 what am I looking at in terms of a general tune up?